1. Field of the Invention
The present invention is directed to water treatment. In particular the present invention is directed to the field of water treatment using clean technology.
2. Description of the Related Technology
Water in processes such as the hydraulic fracturing of shale can contain high concentrations of microorganisms and dissolved inorganic solids. Examples of such water, includes fracking water, flowback water obtained during the drilling phase, and produced water obtained during the production phase. In particular, mineral ions such as calcium and magnesium can cause mineral fouling in the form of calcium and magnesium salts. These mineral salts form hard scale in industrial equipment, such as pumps and heat exchangers, reducing the performance of the equipment.
Fouling is a major challenge in the treatment of produced water. This problem can affect all water-bearing industrial equipment including pumps and heat exchangers. Various chemicals such as acids, lime (Ca(OH)2), caustics (NaOH), chelating agents (citric acid and EDTA), phosphonates, and polyacrylamides, among others, are used to treat water so that mineral fouling can be prevented. These chemicals have environmental disadvantages.
Chlorine and ozone are employed in some conventional methods for disinfection of water containing microorganisms. The use of chlorine has environmental disadvantages. Ozone has the disadvantage of high cost because this method requires a compressor and an ozone injection facility. This equipment increases energy costs as well as capital costs. Ultraviolet light (UV) lamp is also sometimes used for treatment of bacterial disinfection and low turbidity water.
Therefore, there is a need for a method and system for treating water that has a low environmental impact as well as a low cost.